Examples

Each directory is a program that demonstrates one part of casty. They all use the uv project of this directory, which installs the local version of casty from the root of the repository.

Requires uv, Python 3.12 or later and a Rust toolchain: on the first run, uv compiles casty. The commands start from the root of the repository, and each example runs with uv run inside its directory:

cd examples/00-hello-world
uv run main.py

The examples with several nodes start them all in the same process, each on a local TCP port, and stop them when they finish. 09-docker-cluster is the exception: it runs in containers and needs only Docker.

• 00-hello-world: an actor with an initial state, asked with ask, and one state per key.
• 01-state-machine: an order as a state machine, where ctx.become changes the behavior without changing the reference.
• 02-actors-talking: an actor that coordinates transfers by asking other actors through ctx.system.ref.
• 03-streams: ctx.merge joining the mailbox and an async generator in the same loop of the actor.
• 04-failures: ActorFailed, MailboxFull and the state an actor keeps after a failure.
• 05-replication: a state with three replicas that survives the loss of the node running its key.
• 06-distribution: keys spread over the hash ring while nodes join and leave the cluster.
• 07-client: a Client that uses the cluster without being part of it, with each node in its own process.
• 08-consumers: one consumer per partition, which the cluster resumes on its own when its node goes down.
• 09-docker-cluster: a cluster of thirty-three nodes in Docker Compose, resized while it runs.
• 10-agent-per-node: one agent per node, declared with pinned=True and reached by the address of the node.
• 11-durable-state: a state with durable="write" in a SQLite store, which survives the stop of every node.